October sets record high temperatures, record low sea ice

October proved to be a very warm month for Nome, with temperatures high enough to break three daily records, plus one record tie. Throughout Alaska, higher temperatures were seen across the board, even up to Barrow.
According to the National Weather Service, the monthly average temperature in Barrow for the month of October was the warmest on record, at 30.1°F. For the first time in recorded weather history the daily high temperatures in Barrow were on average 33.5°F, above the freezing level.
As high sea surface temperatures combined with a low pressure over the Bering Sea and a high pressure over northern Scandinavia, October weather conditions culminated into a perfect storm of Arctic warming.
From the National Weather Service station in Nome, Christopher Clarke said that preliminary data shows three record high temperatures for the day were broken last month: October 11 at 52°F, October 12 at 59°F and a very warm Halloween on October 31 with 43°F. On October 29, Nome tied the record high temperature with 44°F.
An overall look at preliminary temperature data for October shows that Nome had an average maximum temperature of 33.5°F. The normal average maximum is 21.8°F. Last year saw an average of 23.7°F. To look at the other end of things, the average minimum temperature in Nome last month was 26.7°F. The normal average minimum is 12.6° F, and last year reached an average minimum of 16.6°F.
According to Clarke, the low-pressure system that was parked over the Bering Sea during October has been the main cause of high temperatures across the region.
Things were not just warmer in the air in October, as sea surface temperatures saw unusually high levels over the Chukchi and Beaufort Seas. According to the National Snow and Ice Data Center, or NSIDC for short, these high sea surface temperatures are the main reason behind the unusually slow growth of Arctic sea ice.
The NSIDC reports that in October, the average extent of Arctic sea ice covered only 2.5 million square miles, making it the lowest October sea ice since observation per satellite began. During the first half of the month, from October 1-15, sea ice increased by just 146,000 square miles. That number is less than a third of the normal increase during that period.
As reported by the NSIDC, the Arctic region is losing its oldest and thickest ice. For the average monthly amount each October from 1979 to 2016, the extent of Arctic Sea Ice has decreased 25,600 square miles per year, which equates to a 7.4 percent decrease per decade.
The NWS Alaska Sea Ice Program forecasted on October 26 in their 3-month sea ice outlook that “while the sea surface temperatures in the Bering Sea continue to be above normal… sea surface temperatures across the northern Chukchi Sea are generally primed for new sea ice growth.”
In the Norton Sound region, the NWS predicted that, “new sea ice will begin to temporarily form and melt as storms pass over the region from late October through the second week of November. We expect it to fill into 7 tenths concentration by the fourth week of November.”